Nandrolone is an anabolic androgenic steroid. The use of this substance is prohibited by World Anti-Doping Agency (WADA). In National Anti-Doping Laboratory, we have developed method for quantitative determination of major nandrolone metabolite – 19-norandrosterone in human urine by GC/MS technique (Agilent 7000). Proposed method includes sample preparation of urine samples with enzymatic hydrolysis, liquid-liquid extraction followed by derivatization step with MSTFA. Deuterated 19-norandrosterone has been used as internal standard. Total run time comprised 16 min. Lower limit of quantitation accounted for 1 ng/mL. Spiked urine samples were prepared by mixing blank urine with standard solutions of 19-norandrosterone in range 1–30 ng/mL, correlation coefficient larger than 0.99. Method was verified to following validation parameters: selectivity, linearity, repeatability, accuracy, matrix effect, stability and robustness. Furthermore, measurement uncertainty was estimated. Thus, proposed method is able to detect threshold 19-norandrosterone in human urine and carry out its quantitation conforming WADA requirements.

The extraction of anabolic steroids (1,4-androstadiene-3,17-dione; 17α-methyltestosterone; 19-norethiocholanolone; 4-hydroxytestosterone; 4-androstene-3,17-dione; 5α-androstane-3β,17β-diol; dehydroepiandrosterone; calusterone; clostebol; methandienone; methyldienolone; nandrolone; testosterone; epitestosterone; tibolone; 19-norandrostenedione; 1-methylene-5α-androstan-3α-ol-17-one) by aqueous-organic mixtures from hexane solutions was studied at the temperature (20 ± 1) °C. Based on the experimental data obtained, the partition ratios of anabolic steroids were calculated, which were used to optimise the standard sample preparation procedure in the process of determining the compounds under study in biologically active dietary supplements and specialised sports nutrition. It was found that the most effective and selective extractants from hydrocarbon solutions are water-acetonitrile mixtures containing from 10 to 20 % by volume of water. An extraction technique has been developed for sample preparation of biologically active dietary supplements for subsequent gas chromatographic determination of anabolic steroids in them using a triple quadrupole mass spectrometric detector. The proposed method is characterised by a standard deviation of 10–15 % and a detection limit about 10 μg/kg of biologically active dietary supplements, which makes it possible to reliably determine impurities of prohibited anabolic steroids in them.